Ciphering and deciphering apparatus



March 8, 1932. p, H| TT 1,848,291

CIFHERING AND DECIPHERING APPARATUS Filed Aug. 13, 1930 4 Sheets-Sheet 1 INVENTOR PARKER HITT FIGJ CIPHERING AND DECIPH ERING APPARATUS Filed Aug. 13, 1930 4 Sheets-Sheet 2 N 9 LL.

a \Q g v n f 6 0 INVENTOR l l'll-Ml PARKER HITT N r- I a m 2 March 8, 1932. P. HITT CIPHERING AND DECIPHERING APPARATUS 4 Sheets-Sheet '3 Filed Aug. 13, 1950 Ill om 8 a INVENTOR PARKER HITT March 8, 1932. P. HlTT 1,848,291

CIPHERING AND DECIPHERING APPARATUS Filed Aug. 15, 1930 4 Sheets-Sheet 4 L 7 2 22l :53 QM 102 j Fl G. 4

T Y H; il: 224 2 s 2263 INVENTOR PARKER HITT Patented Mar. 8, 1 932 satires erases earaar series manna mm, or NEW YORK, N. Y; assre'noa r0 murmarxormr. commumcarrous LABORATORIES, mo, or NEW YORK, N. Y., A coaromrron' on NEW 203x CIPHEBING- AND DECIPHERING APPARATUS Application filed August 13, 1930. Serial N'o. 474,972.

cycle being traversed frequently, even in a message of moderate length, it being possible for an expert cryptoanalyst to decipher a message prepared by a machine having a repeating cipher-ing cycle.

- ystems employing key tapes and cipher ing tapes are limited to a ciphering cycle of only a moderate length owing to the practical difficulty of preparing key tapes at each terminal of the circuit. Another disadvantage is that the key tapes must be inserted in the tape transmitters at each station at the same point on each tape so that the code combinations of the enciphered message may be recombined with the same code combinations which caused the enciphering of the message. This has had the efiect of restricting the use of a key tape system to those stations having identical key tapes.

By means of the present invention, any person having a ciphering device such as that about to be described may communicate in cipher with others similarly equipped without resorting to complicated arrangements for preparing and positioning key tapes. It is not necessary for an attendant to be able to read the telegraph code in order to operate this device, as is the case when key tape systems are used.

The invention will be described in connection with the accompanying drawings of which there are five, which illustrate one embodiment thereof. In general, the invention -may be said to comprise a conventional printing telegraph system with a device at each terminal for ciphering and deciphering signals. The printing telegraph may be a startstop or a continuous synchronism system.

The ciphering and deciphering device consists of a novel switching arrangement by which the impulses of a transmitter are altered or left unchanged, depending on the setting of the switching mechanism, which will be referred to hereinafter as a cipher controller. At the receiving station corresponding switching mechanism is employed to decipher the signals. A system of gears, each one of which is associated with a variably notched wheel or disc is used to set a plurality of contact groups. An impulse transmitted to the line depends on the setting of a be set to the same initial position as the one used in preparing the cipher.

Referring to the drawings:

Fig. 1 is a front elevation of the cipher controller with the front cover partly cut away.

Fig. 2 is a side elevation of Fig. 1 with the end cover removed.

' Fig. 3 is a top view of Fig. 1.

Fig. 4c is a diagrammatic view showing the various contact circuits of the cipher controller in connection with the schematic transmitting and receiving station, and

Fig. 5 shows a developed view of a preferred arrangement of ten cams.

Referring to Fig. 1 a shaft 1, having secured to it a series of gears 2 each of which has an equal number of teeth, is shown mounted in suitable bearings 3 and 4 in frame 5. A clock spring contained in a drum 6 tends to rotate shaft 1 through gears 7 and 8; gear 7 forming part of the spring drum and being in mesh with gear 8 which is secured to shaft 1.

pivoted on bearing 11, is held in the path of the teeth on the escapement wheel 9 by"the spring 12 attached to the lower end of the escapement lever, preventing the escapement wheel and shaft 1 to which it is attached from rotating. A magnet 13 has an armature 14 secured to the escapement lever. Each time the magnet is energized, it will attract this armature withdrawin the escapement lever against the tension 0 spring 12, permitting the escapement wheel to advance one tooth. Each gear 2 on shaft 1 is associated with and normally in mesh with a gear 15 secured to a drum 18. In the present embodiment of this invention there are ten drums 18, each of which is a unitary structure having a gear 15 secured concentrically to one side, and a disc 16 having a series of cams 17 (see Fig. 2) on its edge secured to the opposite side. In dividual and independent supporting members 20, (Figs. 2 and 3) each having a bearing 19 on which the drums 18 may be rotated, pivot on a common bearing 21 (Fig. 2). The surface of drums 18 is divided into sections, each section being designated by a letter of the alphabet or by other suitable characters. Levers 22 secu ed to members 20 project through slot 23 in the cover 24 of the cipher controller and each terminates in a key 25. Springs 26 attached to the supporting members tend to raise the keys 25, holding the gears 15 in mesh with gears 2.

' A bar 26 (Fig. 1) is provided with screws 27 which engage the rear of a projecting section 28 (Fig. 2) of the supporting members 20. The screws form adjustable rear stops for the members 20 and may be used to regulate the extent in which gears 15 will mesh with gears 2. A series of slots 29 in the under-side of a bar 30 into which the upper part 28 of supporting members 20 projects, forms guideways therefor. A sliding member 31 slotted at 32 is arranged to slide in a longitudinal groove 33 extending the greater part of the length of member 31. Slots 32 in the sliding member are cut to coincide with the guideway slots 29, but normally the sliding member is drawn to the right by spring 34 which displaces the slot 32 in relation to the guideway slots, partially closing them and forming front stops for extension 28 of member 20, making it impossible to depress keys 25 while 31 is in the right hand position. The teeth 17 (Fig. 5) which are variably arranged about the entire periphery of discs 16 serve to operate a series of contact groups 35 to 44 inclusive (Fig. 1), one group of contacts being associated with each disc. In the present embodiment, the odd numbered contact groups comprise a single tongue 45 which may make contact with either of two outer contacts, 46 and 47, while the even numbered contact groups have two tongues 48 and 49 and three fixed contacts 50, 51 and 52. In the latter case, the tongues 48 and 49 are secured to each other by a piece of insulating material 53 in order that they may be operated together.

Referring to Fi' s. 1 and 2. As drums 18 rotate, each cam 1 54, one of which is positioned between each drum and contact group. The cam followers are pivoted on a common shaft 55. Stop screws 56 are provided to regulate the travel of the cam followers.

' Each cam follower has a strip of insulating material 57 secured to its top to engage the tongues of the adjacent contact groups 35-44. Tooth 58 of which there is one on each cam follower, is drawn into the path of the teeth 17 on the drum associated thereengages a cam follower with by springs 59. The tongues of the contact groups rest on their front or back contacts depending on whether tooth 58 of the associated cam follower rides on an elevation or in a depression. As previously stated, each disc has a series of characters about its periphery. Normally when in service, the mechanism is enclosed by suitable covers, the front cover having a series of openings 60 (Figs. 2 and 3) through which the characters on the respective discs may be seen. In Figs. 1 and 2, oblong strips of metal 61 are shown secured at 62 to a projecting part 64 of supporting member 20. These strips each have an aperture 65 which co-incides with corresponding openings 60' in the cover. smaller openings 65 in the strips serve as guides for setting the discs according to some pre-arranged keyword.

Since gears 15 are in engagement with gears 2 of shaft 1, which is normally held immovable by the escapement, the following arrangement is provided so that the drums may be manually rotated, individually or collectively, so that the letters of the desired keyword appear at the slots in the cover. In Figs. 1 and 3, a shaft 66 is shown, which is free to rotate and move longitudinally in a bearing 67 in the cipher controller frame. A knob 68 is mounted on the outer end of the shaft, and a pinion 69 is secured to the inner end. Pinion 69 is constantly in mesh with a pinion 70 on a shaft 71 which is free to rotate in its bearings 72 and 73. Shaft 71, carries a number of gears 74 each one of which is directly opposite a gear 15 on the drums 18, but normally not in mesh therewith.

The slotted sliding member 31 carries a roller 75 (Figs. 2 and 3) which presses against gear 69, the face of the gear formin a stop for the slide. If the knob 68 is presse toward the frame of the cipher controller, the teeth of gear 69 will slide toward the left hand edge of the wider gear 70 and the face of the gear 69 will press against roller 75, moving the sliding member in its slot against the tension of spring 34. When the knob rests against bearing 67 the slots 32 will coincide with the guide slots 29. When the The slots are thus aligned, any key 25 or any desired group of keys may be pressed (Fig. 2), causing theirrespective supporting members 20 to rotate on shaft 21, moving gears 15 out of mesh with gears 2 and movingthem into mesh with gears 74 on the idler shaft 71. Then, with the keys still depressed and the knob 68 still held in towards the frame of the cipher controller, the knob can be turned to rotate shaft 71 and any of the ears 15 in mesh with the gears 74 thereof. 11 this way the drums 18 may be rotated until the desired character appears at the opening in strip 61. As this occurs the keys may be released, permitting their respective supporting members to move back against their stop screws 27, bringing their gears 15 respectively into mesh again with gears 2.

A diagram of the switching circuits of the cipher controller is shown in Fig. 4 in connection with schematic circuits of a printing telegraph system.

The distributor rings are shown developed for the sake of clarity. The five tongues of a transmitter are represented by 80, 81, 82, 83 and 84. Each tongue has marking and spacing contacts 85 to 94 inclusive, the odd numbered contacts being the marking contacts.

In the present embodiment of this invention, the cipher controller switches are interconnected in pairs, a single tongue switch being paired with a double tongue switch in each case; for example, 35 is paired with 36, 37 with 38, etc. The various contacts of each group pair are connected as follows:

Fixed contacts 46, 50 and 52 are connected together. Fixed contacts 47 and 51 are also connected to each other. The marking and spacing contacts of the transmitter are each connected to one of the tongues of a two tongue contact group. The tongues of the single tongue groups are each connected to a segment of the transmitting distributor ring. For example, marking contact 85 is connected to 48; spacing contact 86 to 49 and tongue 45 to the 5th pulse segment of the distributor. The same arrangement follows for the remainder of the circuits between the transmitter and the distributor segments.

As brush 96 passes along ring 97 and the associated segmented ring, the pole changer will be operated whenever there is a closed circuit from the battery 99 through the transmitter contacts to their respective distributor segments. Each time 100 is energized, negative or marking battery will flow to the line. The pole changer is biased so that the tongue rests on its spacing contact when no current flows through its coils.

At the receiving station the impulses resulting from the position of the transmitter and cipher controller contacts will come in. on solid ring 101 of the receiving distributor. As brush 102 which in synchronism with brush 96 passes along the segments to the tongues of polar relays 103, 104, 105, y

106, 107 will be positioned on their contacts according to the polarity of the incoming impulses. The tongues 108--112 of relays 103-407 have contacts 114-123 inclusive, the odd numbered contacts being the marking contacts. Tongues 108-112 are each connected to one side of a selecting magnet of a receiving instrument which may be a telegraph printer, a receiving perforator or any other similar device. The selecting magnets 124128 have the other side of their coils connected to the negative pole of battery 129. The positive pole of battery 129 is connected to all tongues 45 of the cipher controller at the receiving station. Otherwise the connections of the cipher controller are similar to those at the transmitting station.

Each time the brushes in the respective station have passed over the receiver and transmitter segments, escapement magnet 13 receives an impulse'from some local source which permits the escapement wheel 9 to advance one tooth, advancing at the same time all drums 18 and changing the setting of the cipher controller switches. There are a number of ways for producing a suitable timed local impulse. For example, the cipher controller escapement might be operated from a segment in the local ring if used in connection with one of the various well known multiplex printing telegraph systems. At the receiving station the magnet of the cipher controller could be operated from the so-called' 6th pulse or printing pulse, and at the sending end by the impulse used for ste ping the transmitter along.

local distributor ring 220 connected to a grounded battery 221 is shown in Fig. 4. Associated therewith is a segment 222 and a brush 223. A circuit leads from segment 222 through the coils of escapement magnet 13 and thence to ground. Brush 223 in this case rotates in fixed relation to brush 102 and closes the circuit from battery 221 to the escapement magnet shortly after brush 102 has passed over the five segments connected with the receiving polar relays. A similar arrangement which operates in the same manner is shown at the transmitting station.

Local ring 224 connected to a grounded battery 225 has associated with it a brush 226 and a segment 227. Brush 226 closes the circuit to .magnet 13 immediately after the brush 96 passes over the five transmitting segments.

As previously stated, each of the five pairs of reversing switches is operated by two of the ten gears 15 which are driven by a common pinion shaft 1. In the present arrangement, the two gears controlling each reversal differ by one tooth, the actual gear ratlos being ninety-six and ninety-seven teeth for switches 35 and 36 respectively, ninety-eight and ninety-nine for switches 37 and 38, one hundred and one hundred one for switches 39 and 40, one hundred two and one hundred three for switches 41 and 42, one hundred four and one hundred five for switches 43 and 44. Since they are all driven by a common pinion, it is evident that one gear of each pair will gain one tooth over the other for each revolution, so that the whole cycle for a pair is the product of their tooth numbers, these being in each case prime to one another. Since all five pairs of gears co-operate in ciphering each letter, the cycle for the cipher controller is the product of the prime factors to be found in the five single cycles. In the arrangement shown, the cycle has a length of 6,195,021,558,110, indicating that there are that many different relations of the ten gears, and their associated cams before repetition begins.

For mechanical reasons, the greatest number of teeth per gear should not exceed the smallest number by more than fifteen or twenty, if all gears are of'the same diameter and are driven from a common pinion shaft, but withinthis limitation and that of obtaining the largest number of prime factors, the widest variation in the number of teeth per gear is possible. In the arrangement disclosed herein, it is also evident that, without changing the mechanical construction, the electric Wiring may be changed so that, for example, the ninety-six tooth gear may cooperate with the ninety-nine, the one hundred one, the one hundred three or the one hundred five forming a different pairing of the contact groups, the even numbered tooth gears to operate the other four reversal means. In each such case the two-gear cycles and the whole cycle will be different in. reversing action and in length.

The driving spring contained in drum 6 has its outer end secured to the inside of the drum and its inner end to a shaft 131. This shaft issupported by bearings 145 and 132. Ah

. motor 134 drives 131 through a worm on the motor shaft (not shown) which engages gear 135 fixed to shaft 136. This shaft in turn drives shaft 131 by means of worm 137 and a gear (not shown) WhlCh'iS secured to 131. Shaft 136 rotates in a single long bearing 138. which is part of supporting member 133. Shaft 131 has its middle portion threaded from 139 to 140. A gear 141 threaded internally to fit the threaded section of 131 meshes with a wider gear 143 on shaft 1. A groove 144 in the shoulder 142 of gear 141 engages a at its lower end at 149. CO

pin 147 in the upper end of a lever 148 pivoted A supporting member 150 carrying a small shaft 151 is secured to the base in the rear of 149. A lass tube 152 containing a small quantity 0 mercury and having two wires 161 and 162 sealed in one end is mounted in clips 153 which are in 1 turn secured to a block 154 mounted on one endof shaft 151. A small disc 155 secured to the other end of this shaft has two small pins 156 and 157 on its periphery. The two pins engage two curved springs 158 and 159 'which tend to exert a downward pressure on them. As shaft 1 steps around while the cipher controller operates, pinion 143 turns pinion 141 about on the thre'aded shaft 131, causing ear 141 to move longitudinally on said shaf t in the direction of the motor. The upper part of lever 148 moves along with the gear until the lever presses against spring 159 at 160 pressing the spring away from pin 157. Spring 158 thereupon presses pin 156 downward, rotating shaft 151 at the same time tilting the glass tube 152 so that the mercury runs to the end of the tube in which the two wires 161 and 162 are sealed, forming a circuit between them. This closes the circuit to motor 134 which is normally not operating. The motor drives shaft 131 through the trains of mechanism described above, Winding the driving spring. Since the speed of shaft 131 is greater than that at which pinion 143 can rotate pinion 141, said pinion will move along shaft 131 longitudinally away from the motor, and as lever 148 reaches a vertical position springs 158 and 159 will reset so that they respectively press again on pins 156 and 157. As the lever moves further to the left and as the tension on the driving spring increases,the lever will engage spring 158 at 161, releasing pin 156, causing the glass tube to be tilted in the opposite direction, breaking the circuit between 161 and 162, stopping the motor.

The operation of the cipher controller hereinbefore' described is as follows:

The first three tongues of the transmitter I spacing contacts, which is the combination in the multiplex code for the letter U. The signal transmitted, however, will be governed by the setting of each pair of switches interposed between each transmitter contact and a corresponding distributor segment. Tracing the circuits from the transmitter to the pole changer in order, we find the first transmitter contact 84 on its marking side 93 placing positive potential ontongue 48 of the cipher controller switch 36 associated therewith and fixed contact 50. Switch 35 has its tongue on contact 47 which breaks the circuit to the first distributor segment and consequently, as the brush passes over this segment, pole changer 100 will not operate and the impulse transmitted will be a spacing impulse instead of the marking impulse which would ordinarily be sent out with. the same transmitter setting. The second tongue 83 is also on its marking contact 91 connecting battery through 48 to 51. The circuit to the second segment is open, however, because ton e 45 of switch 37 is on its contact 46 and t e impulse transmitted will be spacing. The third transmitter tongue 82 is on its marking contact 89 and the circuit is completed through 48 of switch 40, contact 51, contact 47 of switch 39, tongue 45, the third distributor segment, brush 96, ring 97, through polechanger 100 to battery 99, operatin the pole changer and transmitting a mar ing impulse. The fourth transmitter tongue is on its spacing contact 88 and a circuit is completed through tongue 49 of switch 42, contact 47 of switch 41, the tongue 45 thereof,

. pulses spacing, and the fourth and third marking, instead of with the first three impulses marking and the fourth and fifth spacing, as this letter would be transmitted without the cipher controller. As brush 102' passes over segments, the tongues of relays 103107 will be positioned according to t e polarity of the received impulses, the tongues of relays 105 and 106 being on the right hand or marking contacts, and those of 103, 104 and 107 on their spacing contacts. The cipher controller switches at the receiving station have the same setting as those at the transmitting station, and the corresponding cipher controller switches at both terminals have the same numbers. Tongue 108 of relay 103 rests on its spacing contact 114 and a circuit may be traced from the positive side of the battery 129 to tongue 45 of switch 35, contacts 47, 51, 49, 114, 108 to magnet 124 to the negative side of battery 129, operating the selecting magnet. Tongue 109 of relay 104 is on its contact 116 and the following circuit is completed: from battery 129, tongue 45 of switch 37, contact 52 of switch 38, relay contacts 116 and 109 through magnet 125 to battery 129, operating the selecting magnet. Tongue 110 of relay 105 is on marking contact 119, operating the selector ma et through a circuit as follows: positive attery 129, tongue 45, switch 39, contacts 47, 51, 48, 110, 119, magnet 126 to negative side of battery 129. Though the fourth relay 106 is to marking, magnet 127 will not" be operated as the circuit is open at contact 46 in switch 4;. The fifth relay 107 is on spacing and the magnet will not be operated as the circuit is open at contact 47 in switch 43..

Since selector magnets 124, 125 and 126 are operated and 127 and 128 are not operated,

the letter U will be recorded by the receiver. After the selectors are operated, cipher controller escapement magnets 13 at each stationwill receive an impulse from the local distributor ring which will cause the setting of the cipher controller switches to be changed so that the next character will be ciphered and deciphered by an entirely different arrangement of circuits.

What is claimed is:

1. In a ciphering system, the combination of a selecting device, a plurality of reversing means co-operating therewith, and means comprising cams and gears for variably operating said reversing means.

2. In a ciphering system, the combination of a selecting device, a plurality of reversing means co-operating therewith, and means comprising cams and gears for variably operating said reversin means, the ratio of each ear to the driving means therefor being different from the ratio of any other of said gears to its driving means.

3. In a ciphering system, the combination of a selecting device havinga pluralit of selecting elements, one for each unit of t 6 code representing a character, reversing switches in circuit with each selecting element, and means com risin cams and gears for vari-- ably operatin sa1d switches.

4. In a cip ering system, the combination of a selecting device having a pluralit of selecting elements, one for each unit of t e code representing a character, reversing switches in circuit with each selecting element, and means comprising cams andgears for variably operating said switches, driving means for said gears, the ratio of each gear to the driving means therefor being different from the ratio of any other of said gears to its drivmg means.

5. In a ciphering system, the combination of reversing means com rising a plurality of reversing switches, a p urality of cams for operating said switches, gears for driving said cams, there being one gear for each cam, and driving means meshing with said gears, the relation between said gears and said driving means being such that no two of said gears have the same peripheral speed.

6. In a cipherin system, the combination of reversing swi es, a cam for operating each switch and having a distinctive cam surface differing from all the other cams, a gear for rotating each cam, and a common driving gear meshing with said cam rotating gears,

the ratio of each cam rotating gear to said havin having a difierent ratio, and the ratio of each group being different from that of the other groups.

8. In a ciphering system, the combination of a plurality of reversing switches, and a gear driven cam for operating each of said switches, said gears being arranged in pairs having different ratios and each cam having an operating face difierent from the others.

9. In a ciphering system, the combination of a plurality of reversing switches, and a gear driven cam for operating each of said switches, said gears being arranged in pairs different ratios, the ratios being such that they contain relatively large prime numbers, and no two of the cams havlng like op erating faces.

10. In a ciphering system, the comhination of a plurality of reversing switches, and a gear driven cam for operating each of said switches, said gears cooperating in grou 5, said groups cooperating with each otheri t e ratios of the respective groups difi'ering from each other and containing large prime numbers, and no two of said cams having like operating faces. 7

11. A ciphering and deciphering device comprising a driven shaft, escapement means for regulating the rotation of said shaft, gears having ifierent ratios rotated by said shaft, a cam controlled by each of said gears, and means operated by said cams for ciphering and deciphering.

12. A ciphering and deciphering device comprising a driven shaft, means for regulating the rotation of said shaft, ears driven by said shaft, the ratios been gears and said driven shaft being difi'erent in each case, a cam member controlled by each of said gears, and means operated by said cams for ciphering and deciphering. 0

13. A ciphering and eclphernig device comprising a driven shaft, means for regulating the rotation of said shaft, gears driven by said shaft, the ratio of said gears and said driven shaft being difierent in each case, a

} variably notched member controlled by each of said gears, and means operated by said variably notched members for ciphering and deciphering. i

14. A ciphering and deciphering device comprising a driven shaft, means for regulating the rotation of said shaft, gears driven by said shaft, the ratio of said gears and said driven shaft being different in eachicase, a cam member controlled-by each of said gears, and means comprising a plurality of contacts operated by said cams for ciphering and deciphering.

15. In an enciphering system, a transmitter having aplurality of pairs of contacts, a ciphering devlce comprising afirst and a second switch corresponding to each pair of contacts, said switches having tongues and fixed contacts and each switch being indea ciphering device comprising a pair of reversing switches for each pair of contacts and means to control their setting, a line, and

circuits interconnecting the switches of each pair, one of the switches of each pair to the line and the other switch of each pair to one of the pairs of contacts of the transmitter.

17. In a deciphering system, a line, a plurality of line relays operated by enciphered signals, each line relay having a tongue and front and back contacts, a ciphering device comprising a pair of co-operating reversing switches for each line relay and means to control setting of each switch, a receiving device and circuits connecting the fixed contacts of the line relays to the movable contacts of one switch of each pair, interconnecting the fixed contacts of the switches of each palr, and connecting the receiving device to the tongues of the line relays and to the movable contacts of the other switch of each pair.

18; In a ciphering device wherein a plurality of gears are driven from a common driving means, means for settingany one of said gears independently in relation to the others comprising means for disengaging the said one gear from said driving means and thereafter meshing the said one gear with a manually operated gear shaft.

19. The method of positioning gears in relation to each other which comprises disengaging one or more said gears from a driving gear and the bringing said disengaged gear or gears into mesh with idler ears and rotating said idler gears until the rst mentioned gears are in the desired relative position and then meshing said first mentioned gears again with said driving gears.

- In witness whereof, I hereunto subscribe my name this 12th day of August, 1930.

- PARKER HITT. 

